Abstract 80: Toward best practices for B-cell receptor repertoire profiling

Abstract FDA anticipates that immune cell receptor profiling will become crucial to the Agency’s evaluation of the efficacy and safety of emerging cancer immunotherapies and immunomodulatory drugs by advancing precision medicine and providing orthogonal, functional evidence. High-throughput sequencing of B-cell receptor sequencing (BCR) gene rearrangements and downstream analysis empowers researchers to define the B-cell clonal landscape, as well as identify biomarkers for minimal residual disease (MRD). Although this field has made vast strides over the last decade, it lacks standardized assay controls, adequate sensitivity and specificity in gene mapping/alignment, and appropriately qualified reference data sets, materials, and validation methods. Moreover, detailed comparisons of wet-bench analytical methods or bioinformatic procedures have not appeared. The FDA led B-cell receptor sequencing quality control (BCR-SEQC) consortium is establishing protocols for the development of reference materials and data sets for the evaluation of NGS-based BCR repertoire reconstruction. The consortium is also developing materials for performance bench-marking studies. To this end, we performed whole-genome sequencing, RNAseq, and BCR-seq on 50 B-cell lines to determine the clonotype, full-length transcripts, and expression abundance of BCR genes in each cell line. Two batches of reference materials (DNA, RNA, and cells) were generated from each of nine cell lines that were determined unambiguously to be monoclonal in BCR expression of both heavy and light chains. These materials were distributed to ten companies to test up to 15 BCR-seq products. Our benchmarking studies include six widely-used sequencing technologies. The overarching objectives of this research were to elucidate current capabilities and limitations, address fundamental technical needs, provide reference materials and data sets, and establish actionable best practices for reconstructing B cell receptor repertoires from NGS data. Citation Format: Wenming Xiao, BCR-SEQC consortium. Toward best practices for B-cell receptor repertoire profiling abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 80.